Engine for rock-drills.



' Bl HAS'IINGS. ENGINE FOB. ROCK DRILLS.

' APPLIOATION HLBDMAYe, 1909. 1,015,798.

1. uu Usw Patented Jan. 30, 1912. y

,12E/venan' i @i 5f l ZJ .J WU j@ nlm "IIE-mn..

which lRock-Drills, of which the following UNiT'ED STATES IPArnisri2 OFFICE.

Anrnmnuuun HAs'rI'Nes, or namsnn'ron, omo.

ENGINE' FOR ROCK-DRILLS.

`Svpecication .of Letters Patent. lApplication led May 6, 1909. Serial No. 494,426.

916,703, issued'March 30, 1909.

The principal object of this inventlon 1s to improve the engine of al rockdrill, and

specific description of its features will be made in the specification below, withv reference to` the accompanying drawings, in

Figure 1 is a general elevation illustrating a preferred form of drilling apparatus with which my invention is shown, in operative position. Fig. 2 is a vertical section ofthe engine taken on two'planes meeting at an angle ofv 120 degrees as shown bythe line `2-'2'of Fig. 3, the wearing ,covering of the ribs being omitted.A Figs. 3 and .4 are en larged transverse sections taken' respectively on the lines 3--3 and 4.-"-4 of Fig. 2. Fig.v

5 is an enlargement'ofthe `valve and valve chest structure shown in Fig. 2.

Referring to the drawings for the details,

it will be seen that the drill involves the useI Y primarily of abody composing an engme barrel A and an outer casingA. In the'upper end of the engine barrel is placed the controlling valve B mounted in a chest B fitted into the interiorly tapered upper end of the barrel.

In the lower end of the barrelis a piston hammerC which strikes upon the upper end of a drill bit D having a free reciprocation within suitable limits at the lower' end of' the drill. To the upper end 'of the barrel is secured, by means of ascrewthread and For the purpose of securingthegrst han-v suitable lock, a handle sectionl E which is a` hollow pipe through which the motive liu'id is conveyed to thev engine. Succeeding pipe Fig. 1,:

sections E are added, as shown `1n within the limitations imposed both by the height of the tunnel or overhead room within which the work isfbeing conducted and also'by the depth of hole required.

The type of drill to which my improvef` l ments are particularly applicable is that ge nerically described' in my prior' Patent No.v

dle section E to thedrill I extendthe upper endof the barrel Abeyond the outer casing end ofthfe barrel is providedwith an lin- Pa'tentea Jam-30,1912.

'in order` that its wall may be thickened and have great strength at the zone A2 where. it. 1s joined to the handle section. The upper terior screw Vthread which receives a corref lspending thread on the lower end of the handle member E, the said 'handle member screwing down iirmly upon a'packing E",

see Fig. 5, interposed between it and a metallic ring B2 on top of the valve chest.

Beneath the handle end and the 'ring B2L against which it presses' is the valve chest rel extending substantially the length of the chest, as shown in Fig. 5. This' method of securing the'v'alve and its housing in position is quite important as by this means I am enabled to obtain, better than by any Aother means, an .air tight tit between the` walls of the chest 'and the barrel and thus avoid leakage between the various ports..

Further, upon release ofthe chest from position itl comes away from its seat without dragging' and scoring-the walls to which it is fitted, thus vpresenting an' adyantage over any other method of securing it in place.

AB".- fIhis chest 'is tapered tofhave a driving fit with the corresponding taper in the en-y v vgine barrel A, the taper of the engine bar- Immediately above the chest will \be i and constant communication through a port B4v with the motive iuid supply, 4the said.

channel, being in the present structure formed in the 'annular vring B2 interposedl between the chest and the end of the handle. Communicating with'this channel are two ports A4, A each extending through the engine barrel, and r so located .that they ""noted an v.annular channel ,B? having free l communicate with'- longitudinal channels or conduits A6' and A7 respectively, on the in-v terior wall of the drill casing A. The two longitudinal channels referred to are shown 'as substantially 120 degrees apart and each of them communicates `at the lower end by means of a port A1. through the engine barrel with the chamber in whicl'i the body of the piston hammer'tCv slides. A peripheral channel C'. on the body ofA the piston hammer coincides with-the zone of these ports when said piston hammer is atV the bottom ofits stroke, tlmseaiording a means of com-,f

munication between the "-two longitudinal conduits A6 and A7. 'One of these conduits has its upper port A, through ithe engine E barrel, of Asuch size as A,to thelive ino-v vtive fluid freely from the hollow handle through which the i'uid pressure' is supplied. The other of said conduits 'AT has its port Af through which such communication 'is established,l of such small diameter as to a/ford but aslowv transmission of pres 4sureto the conduit, for a reason to be subv -v sequently pointed Out. y This last named conduit-A7y communicates, through an openl ving' A8 in the enginebarrel, and a conduit chest, wlth the space inthe valvefche'st-bev--, neath the "controlling valve B. The -lowe'r' exposed to the full iuld pressure; vv'heneverV the vpiston hammer its lowest position,

end of thev controlling valve-thus-becomes and communication established between the upper end of the controlling valve is cpn#v stantly exposed-'to the livepressure coming 'much as the superficial areal 'of the lower end4 ofthevalve is greater than' that of fthe] upper end, the valve will alwaysbe thrownl upward when the pistonhammer is inits':

muni 'cation"lthroughv two ormorellperfor tions A12?,asshowm vwith the outsidexatm'os1. jphere through the valve chest B', VAthe ien- -g-ineL; barrel A and the casing A. The adl i" 'mission-oflive'pressure-to theconduit A? t'akes placefthrough a series of transverse v openings Bs' in thefupper. wall :of thefvalve,

y i langes ;v.' and vj the proportions yof the' p'arts, l are -so arranged that th'e'live pressure is admitted tojf.

hesaid longitudinal channel Aldlrotigh port fA1zwhen the -valv'egis 'at 1 the upper .position andis "cut ofi by one v of the lianges'- BB1 when the valve is at vits' l'owe'rr position; ASimilarly, the exhaust portAfis tion aiid open vwhen thevalve lis at'its lower,

6 5 an 'annular .channel v131e@and"parjta- Bein; a

position. The Idetail 4'of this 'arr: i-ngeinent- -isg as theoperative elect relformsgiuit communicatingthroughl disk B12 atthe lower end, of the chest, with thev piston chamber labove the head of the' `piston hammer. Thisgroove inthe wall 0f- -the'valve chest serves', by means ofa port 'B13 at thenpper end thereof, communicat,

' ing with the upper end of the valve chamber, to admit live pressure into .the piston ychamber when the valve` is in its lower po-` sition. The admissionof such pressure is .cutoff-bythe' valvewhen it 1s in vits upper position. A v second 'j 'poit B2" through the Iwall ofvv the lval\ re :che'st' places this: groove m A commi'u iication f with the exhaust space- B".`

'in the interniediate .portion of the' valve :chamber.'k Thiygzlast named fjportz is opened o that the-chamberabovethe pistoniheadisin 'communicatiomwiththeexhaust;at-jthetime 'said vlv *iS in' its. lower position. For thepurpose fof elievi gv "beneath'thelower endof the valve." and per-f -mittfing'eit'- tofbethrownto'iits :lower :position .effer- -he Pisten' 'hemmen which communicates' wltli beneath 1 the controllingvalv austport- 1s :thev controlling {valvejinthis 2manner will,

as Valzpove.state d' 1 admit` live pressure' above :1 'l' thejl piston: head] andvagain vdrive the piston live pressureand. thelower side of the valve 'establishing j: communication, between the "indicated,- l thelive pressure again be.-

n'e'ath the valve,i t'wi ll be raised in the operationand repeatits'elflif I havey found,' how 'gqui'redf'for tran ssion lof the live pressure :tothe lower face of the valve owingto thefact that the1 distance of transmission' is rather -longand .tothe fact that the longitudinal conf-fduit Admmediatel communicatingtherewith is in a, state o exhaustion which f must bev changed-to azs'ta'te of pressure before the.

operation takes lace.' Ihave discovered-that f :thisislowness vo faction maybe overcolneby'.`l y'creating a communication' betweenthelive 1 25 smh-schmaler. estoi-admita Smau amount.

teraisefthapressnre:therein mfthepeint a y For this purpose I Aprovide the'small opening A at the upper end `of the conduit through the engine-barrel into the live pressurespace at the 'upper end of thevalve schest. I have found that' this overcomes. the .difficulty noted, perfectly, and the comparatively-'small leakage of iiuid therethroughl does not raise the pressure in the conduit quickly enough, after it has been, once exhausted, to throw the valve prematurely, but it will raise the pressure therein suficiently to assist in the quick throwing of v the valveafter the full pressure has been admitted'to the .conduit through the annular vchannel -C about the middle of the piston body.

n win bex noted that I im@l devised a structure-of valve and valve chest which is of material assistance in reducing'the diameter ofthe engine to the lowest possible point, bearing in mind that thewalls should be of a given thickness. By placing'the valve eccentrically in the body of the valve rlao.

flow of fluid toand from t ve upper end chest as shown in Fi s. 2 and l3, I secure a sufficient thickness o metal at one side, in addition to that thickness required-for the walls yof the chest', 'to enableme to place the groove B11 in the exterior wall thereof, which, in conjunction with the inside wall of the barrel, forms a passa eway for the ofthe piston chamber., This is a feature .of construction which is of vimportance where a given thickness is maintained in the walls of the chest and the barrel with a given area of passageway required. It will be observed that-the passageway in question is of some considerable width, and in --order to prevent thel crushing in of the barrel at this point, I have provided a transverse support or brace in the disk B12 for the wall at the lower end of the channel-way B11, substantially as shown. The manner by which I have accomplished this does not in Aany man-J ner obstruct the free iiow of Huid into the chamber. I would at this point call attention to thef fact that the conduits between lthe valve chest and the piston chamber are formed on the interior wall of the drill 'casing immediately beneath .a portion thickened to form exterior ribsA which are provided i "for spacing the drill casing fromthe walls -of the'hole being drilled. The presence of the ribs is advantageous for the purpose Vof scraping the walls of the hole being drilled and for concentra-ting the exhaust air in vertical columns as it passes out ofthe hole,

thus giving it sufficient velocit-y to carry outl the debris froins the lower end of the drill and provide for the conductof air between 1 the valve and the piston with a reduction in the diameter ofthe outside circumference of the casing equivalent to twice the thickness f the' .wall of the vcasing in comparison with other possible arrangements having the same area of passageways and same. diam# f eter .of piston. Inasmuch as the thickness! necessitate. This covering'isshown in the present `instance as applied to the exterior ribs only, these ribs obviously being the part subjected to the greatest wear.

The drill bit'Ds held at'the lower end of the apparatus in such manner as to receive the full blow of the piston hammer and to have free longitudinal play within pre,- 'f

scribed limits. i i

While it is not absolutelyessentiah nevertheless, I prefer, as I have indicated in the drawings, to providethe several handle sections wlth exterior ribs similar to those provided on .the drill casing, the object ofthis being to concentrate the outward flow. of v the exhaust land thus cause it to better clear away the debris.

Having thus described invention, I claim: I

1ly Adrill comprising al piston and an engine barrel interiorly tapered near its rear end, a tapered valve chest containing a controlling valve land litted .to said tapered portion ofthe barrel.

' 2.` A drill having an lengine barrel and a valve chest in the rear end of said barrel, a

valve 'chamber in said chest located eccentricallyrelative thereto, a kfluid conduit in that wall of the chestthickened by location of the, valve chamber.

3. A drill'having an engine barrel and a. valve. chestin the rear end of said barrel, a valve chamber in said chest located eccentrithe eccentric cally relative thereto, and Ia fluid conduit formed on the face of the exterior wallof the valve chest substantially on that dia-meter of the valve chest passing through the axis of the valve chamberv and on theface farthest removed from the valve chamber.

4. .A drill comprising a piston; and anq engine barrel interiorly tapered near its re'ar end,- a vtapered valve'chest containing .a controllingvalve and fitted to said tapered `porvtion of the barrel, and supporting means for l tile Wall `of the lbarrel at the forward end o t.

e valve chest for preventing the pinching; in or collapsing of said barre 5. A drill having a controlling valve, a conduit communicating with -one side of said valve, means for admitting live'pres- 4sure to said conduit to such extent as to operate the valve, and means for exhausting 4", y .A j 'Loic-798 Said 'conduit-and additional 'means .foriadulickened''by4 Said ribgsaid channelsbeilg n yI nstinglive pressure to said conduit slowly`v dapted toconduci'l the motive fluid.v

to assist in the ready operation of the valve Intestimonywhereof, I hereunto afx my- I'substantially .as described. signature infthe presence of two Witnesses.

sections, an vinner barrel and .an outer casf 6.' A drill having a` body composed oitwo BENJAMIN I IAS'IINGYS.k

ing, said outerca-sing having longitudnall-Wfnessesz rbs' .on'v the exterior Wall thereof and chanfl J. M. VVooDWfn, f nelson thejnteror Wallwherethecabsilngis H. R. SU1,L*1VAN. 

